The hydroconversion of both crude and residual oils in an upflow ebullated bed reactor to produce desirable light oil and gaseous product streams is well known, having been disclosed by various U.S. Patents, e.g., U.S. Pat. No. Re.25,770 to Johanson, U.S. Pat. No. 3,291,721 to Schuman and U.S. Pat. No. 3,412,010 to Alpert et al. Another product from such hydroconversion reactions is the heavy vacuum bottoms 975.degree.F plus or higher boiling pitch material which contains a significant proportion of the sulfur originally found in the oil feed stream. This heavy residue material has heretofore been either fed to a coker or blended in with the fuel oil products. However, as the permissible sulfur content of fuel oil products have been progressively lowered below 0.5 wt. percent due to air pollution restrictions, progressively less of this heavy pitch material can be utilized in the low sulfur fuel oil product. The result is that this heavy, high sulfur material has heretofore either been used as in-plant fuel which is no longer permissible, or applied to uses having low economic value.
There has usually been a lack of adequate supply of inexpensive hydrogen needed for hydrotreating the crude oil or residuum feed streams in the hydroconversion process. However, no convenient way has heretofore existed for using this heavy sulfur-containing residue material to alleviate the hydrogen shortage problem.